There has hitherto been known a damper device that includes a first elastic body that transfers torque between an input element and an output element, a second elastic body disposed on the inner side of the first elastic body to transfer torque between the input element and the output element, and a dynamic damper that has a vibration absorption elastic body coupled to any of rotary elements that constitute the damper device and a mass body coupled to the vibration absorption elastic body (see Patent Document 1, for example). In the damper device, the vibration absorption elastic body which constitutes the dynamic damper is disposed on the outer side or the inner side, in the radial direction, of the first and second elastic bodies, or between the first elastic body and the second elastic body in the radial direction.
There has also hitherto been known a fluid transmission apparatus that includes a pump impeller connected to an input member, a turbine runner that is rotatable coaxially with the pump impeller, a damper mechanism connected to an output member, a lock-up clutch that engages the input member and an input element of the damper mechanism with each other, an elastic body disposed between the turbine runner and a first element, which is any one of a plurality of elements that constitute the damper mechanism, so as to abut against the turbine runner and the first element, and an engagement mechanism disposed between the turbine runner and a second element, which is one of the elements which constitute the damper mechanism other than the first element, to engage the turbine runner and the second element with each other so as to rotate together with each other (see Patent Document 2, for example). In the fluid transmission apparatus, when the input member and the input element of the damper mechanism are engaged with each other by the lock-up clutch, the elastic body constitutes a dynamic damper together with the turbine runner which serves as a mass that does not contribute to torque transfer between the input member and the output member. When the turbine runner and the second element are engaged with each other by the engagement mechanism to rotate together with each other, in addition, the elastic body between the turbine runner and the first element functions as a damper that absorbs torque between the input member and the output member. Consequently, in the fluid transmission apparatus, the elastic body between the turbine runner and the first element can be used as both an elastic body for the dynamic damper and an elastic body that absorbs excessive torque input to the input member.